Health Library

When You Need a Blood Transfusion (Adult)

A blood transfusion is often done when a person has lost blood because of an injury or during surgery. It can also be done because of diseases or conditions that affect the blood. Blood is made up of several different parts (blood products). You may receive some or all of these blood products during a transfusion. Blood for transfusion is usually donated from another person (donor). Strict measures are taken to make sure that donated blood is safe before it’s given to you. This sheet helps you understand how a blood transfusion is done. Your health care provider will discuss your condition with you and answer your questions.

The Parts of Blood

Blood can be broken down into different parts that perform special roles in the body. These parts include:

Red blood cells, which carry oxygen throughout the body.

Platelets, which help stop bleeding.

Plasma (the liquid part of blood), which carries red blood cells and platelets throughout the body. Plasma also helps platelets in stopping bleeding.

Where Does Donated Blood Come From?

Volunteer donors. These are people who donate their blood to help others in need of blood. Blood donation can take place at several places, including a hospital, blood bank, or during a blood drive.

Directed donation. A person may need a blood transfusion during a planned surgery. Family and friends can have their blood tested for compatibility and donate blood for the patient before the surgery. This needs to be done at least 7 day(s) in advance. This is because the blood must be tested for safety.

Autologous donation. This is also called self-donation. For planned surgery, a person can donate his or her own blood starting up to 6 weeks before surgery. Doctors often recommend this kind of donation because it is the safest, since the patient’s own blood is used for transfusion.

Are Blood Transfusions Safe?

Except for self-donated blood, all donated blood is tested and processed to make sure that the blood is safe:

The health and medical history of each donor is carefully screened. If a person is considered high-risk for infection or problems, he or she isn’t accepted as a blood donor.

Donated blood is tested for infections such as hepatitis, syphilis, and HIV (the virus that causes AIDS). If the tested blood is found to be unsafe, it’s destroyed.

Blood is divided into four types: A, B, AB, and O. Blood also has Rh types: positive (+) and negative (-). You can only receive blood products that are compatible with (match) your blood type. A sample of your blood is tested for compatibility with donated blood. This is done before blood products are prepared for a transfusion.

How Is a Blood Transfusion Done?

A blood transfusion takes place in a blood center, hospital room, or operating room. It usually lasts 1–2 hours. Your health care provider will discuss the blood transfusion with you before it’s done. You’ll need to give permission for the blood transfusion by signing a consent form.

Two health care providers confirm your identity. They also confirm that they have the correct blood product(s) for you.

An intravenous (IV) line is placed in a vein if you do not already have an IV.

The blood product comes in a plastic bag that is hung on an IV pole. The blood product flows from the bag into your IV line. The IV line may be connected to a pump, which controls the transfusion rate. You may receive more than one kind of blood product through the IV.

Your vital signs (blood pressure, heart rate, respiratory rate, and temperature) are checked throughout the transfusion. This is to make sure you are not having a reaction to the blood product.

The IV line may be removed once the transfusion is complete.

Possible Risks and Complications of Blood Transfusions

Most transfusions are problem free. In some cases, reactions occur. These can happen within seconds to minutes during the transfusion or a week to a few months after the transfusion. Call your doctor or nurse right away if you have any of the signs or symptoms in the table below during or after a transfusion: